Jane Muthoni Mara said she felt "completely and utterly violated" after sexual torture.
She is demanding compensation for her suffering.
Jane said: "I want the British citizens of today to know what their forefathers did to me and to so many others. These crimes cannot go unpunished and forgotten."
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PM used a speech in Hamburg to say that the UK will not 'pull up the drawbridge and retreat from the world' but Europe must change.
It is set to remain unsettled into Saturday, becoming drier on Sunday.